Gauge block
Bloque patrón
- Date
- 1896 · confidence high
- Place
- Eskilstuna, Sweden
- Credited to
- Carl Edvard Johansson
- Field
- Knowledge & symbols
What it is
A system of metal or ceramic blocks ground and lapped to a precise thickness that, stacked and joined by wringing, produce exact reference lengths to calibrate micrometers and other shop instruments.
Also called Johansson gauges or "Jo blocks"; thirty blocks from one set can be combined to make all 1000 lengths from 3.000 to 3.999 mm in one-micron steps.
What it led to
- The main dimensional-calibration standard in industry
- Metrological traceability in precision workshops worldwide